Exercise device



FIG. 1 is an isometric view of the design; user attachment belts are shown in dotted outline and do not form a part of our ornamental design;

FIG. 2 is a front view of the design;

FIG. 3 is a rear view of the design;

FIG. 4 is a top view of the design;

FIG. 5 is a right side elevation view of the design; the left side elevation view being a mirror image thereof; and,

FIG. 6 is a bottom view of the design. 

The ornamental design for an exercise device, as shown and described. 